The International Cricket Council (ICC) has told leading international players taking part in the 12-team event to agree to contracts prohibiting them from endorsing companies that are rivals to its commercial sponsors.
Players from South Africa and India have argued that the ICC contracts will violate their existing sponsorship deals but 10 nations' teams, including England and Australia, have agreed to sign the contracts.
According to some reports from Johannesburg, the country's top players may now decide against making the trip.
But the United Cricket Board of South Africa (UCB) said it was confident the matter would be resolved.
